Installing new Phoenix water heater, expansion tank too?

[jbiddle]

I'm about to have a contractor replace my standard 50 gal hot water heater with a high efficiency tank type (HTP Phoenix LD 50 gal) and I'd rather decide what I want installed instead of leaving it up to him (of course his input will be considered). Last year I replaced replaced my HVAC with a high efficiency model and my water heater is now orphaned on the stack. My current water system does not have either a mixing valve or an expansion tank and I'm thinking of having both installed with the replacement. Here is my water meter; I think the device on the output is a residential dual check?




Would the Caleffi mixing valve with gauge and checks (#52519AC) model be a good choice. My intent is to set the water heater at 140 and the mixing valve at 120. If it matters, I want to leave open the possibility of adding a recirculating system in the future.

Also, my dishwasher has it's own heating element and my high efficiency washer has a heater for sanitizing (mostly I wash with cold or warm water) so I don't think I'll need to pipe any hot water directly from the heater, do you?

Is the Therm-X-Trol ST-5 a good choice ? My water pressure is at 65psi now but I've seen it fluctuate from 45psi to 80psi over the years.

Is there any benefit to installing the water heater on a riser (basement location)?

Thanks in advance for your help.

 

[Smooky]

It looks like a regluar straight meter coupling to me. Hire a professional in your area and see what he says.

http://www.fordmeterbox.com/products/productview.php?catSec=H&subSec=Meter Couplings&heading=Straight Meter Couplings&table=C38

http://catalog.muellercompany.com/C...PE-PJ-IPS-PE-CS-FIP-MIP-582-meters-Pg-8E2/330

https://www.google.com/search?q="Straight+Meter+Couplings+"&lr&hl=en&as_qdr=all&tbm=isch&imgil=k8E21jXYE-2CIM%3A%3B_v2dTh2cEMJv7M%3Bhttp%253A%252F%252Fwww.aymcdonald.com%252Fen-US%252FNo-lead-Straight-meter-couplings.html&source=iu&pf=m&fir=k8E21jXYE-2CIM%3A%2C_v2dTh2cEMJv7M%2C_&usg=__1Eczaz1657W4X2X0jccVFH9ah_M=&biw=1152&bih=554&ved=0ahUKEwjY2Yzf4bvLAhXBUyYKHfyXAsAQyjcIMw&ei=CV7kVpixGcGnmQH8r4qADA#imgrc=_

 

[Sponsor]

 

[jbiddle]

You're right, it is a coupling. I'll ask the plumbing inspector on Monday what if any check will be required because of the rework.

 

[Jadnashua]

Codes change, so it's hard to specify what may be required for that. If you do have a closed water system, and even if you don't now, the water utility company may install one some time in the future, an ET is not a bad thing to have, and a tempering valve is a good safety device to have.

But, where I live, you are required install a vacuum breaker, a mixing valve, and an expansion tank to pass code for any new WH install.

 

[jbiddle]

Would this be the correct vacuum breaker, should one be needed? http://www.supplyhouse.com/Watts-0792039-3-4-LF288A-Anti-Siphon-Vacuum-Breaker-Lead-Free

 

[Jadnashua]

Not familiar with what's out there, but that seems like it would be fine. Note, while code is sometimes nearsighted, in reality, unless the tank is up fairly high (some people put them in the attic), it is not likely that a vacuum breaker would be needed to help protect the tank from damage. It won't hurt, and it's code where I live, but it's hard to cause damage when it is say in the basement, and the drain is right there...there's little height to create a significant suction. The tanks are designed to handle decent pressure, but not vacuum.

 

[Smooky]

You might need a "Dual Check Valve" at the meter:
http://www.homedepot.com/s/DualCheck%20Valve?NCNI-5

The anti siphon vacuum breaker in your link does not prevent back pressure it only prevents back siphonage.

This type of Vacuum Relief Valve is used on tanks such as hot water heaters:
http://www.supplyhouse.com/Zurn-34-VR10XL-3-4-VR10-Vacuum-Relief-Valve-MNPT-Lead-Free
http://www.supplyhouse.com/Watts-0556031-3-4-LFN36M1-Lead-Free-Water-Service-Vacuum-Relief-Valve?gclid=CL7FgZzrvssCFdU7gQodp4IGuA